Survival in Alzheimer's disease and vascular dementias.

Over 5 years, we followed 199 patients with dementia of the Alzheimer type (DAT), 69 with multi-infarct dementia (MID), and 43 with mixed dementia (MIX). All three diagnostic categories had comparable progression of behavioral and cognitive impairment and need for home care or institutionalization at follow-up. However, 50% survival from diagnosis was 2.6 years for MID and 2.5 years for MIX, compared with 3.4 years for DAT. The 50% survivals from onset were longer than previous reports would suggest (8.1 years for DAT, 6.7 for MID, and 6.2 for MIX). Vascular dementias have higher mortality than DAT, even when associated with comparable cognitive and behavioral impairment.